1School of Acupuncture and Moxibustion and Tuina, Beijing University of Chinese Medicine, Beijing 100029, China2Chinese Astronaut Scientific Research and Training Center, Beijing 100094, China3Department of Family and Community Medicine, Center for Integrative Medicine, School of Medicine, University of Maryland, Baltimore, MD 21201, USA

Received 1 February 2013; Revised 10 April 2013; Accepted 29 April 2013